Most vertical takeoff and landing aircraft rely on gyro stabilization systems to remain stable in hovering flight. For instance, applicant's previous U.S. Pat. No. 5,971,320 and International PCT application WO 99/10235 discloses a helicopter with a gyroscopic rotor assembly. The helicopter disclosed therein uses a yaw propeller mounted on the frame of the body to control the orientation or yaw of the helicopter. However, different characteristics are present when the body of the toy, such as a flying saucer model, rotates as gyro stabilization systems may not be necessary when the body rotates, for example, see U.S. Pat. Nos. 5,297,759; 5,634,839; 5,672,086; and co-pending co-assigned U.S. patent application Ser. No. 09/819,189.
However, a great deal of effort is made in the following prior art to eliminate or counteract the torque created by horizontal rotating propellers in flying aircraft in order to replace increased stability by removing gyro-stabilization systems. For example, Japanese Patent Application Number 63-026355 to Keyence Corp. provides a first pair of horizontal propellers reversely rotating from a second pair of horizontal propellers in order to eliminate torque. See also U.S. Pat. No. 5,071,383 which incorporates two horizontal propellers rotating in opposite directions to eliminate rotation of the aircraft. Similarly, U.S. Pat. No. 3,568,358 discloses means for providing a counter-torque to the torque produced by a propeller because, as stated in the '358 patent, torque creates instability as well as reducing the propeller speed and effective efficiency of the propeller.
The prior art also includes flying or rotary aircraft which have disclosed the ability to stabilize the aircraft without the need for counter-rotating propellers. U.S. Pat. No. 5,297,759 incorporates a plurality of blades positioned around a hub and its central axis and fixed in pitch. A pair of rotors pitched transversely to a central axis to provide lift and rotation are mounted on diametrically opposing blades. Each blade includes turned outer tips, which create a passive stability by generating transverse lift forces to counteract imbalance of vertical lift forces generated by the blades, which maintains the center of lift on the central axis of the rotors. In addition, because the rotors are pitched transversely to the central axis to provide lift and rotation, the lift generated by the blades is always greater than the lift generated by the rotors.
Nevertheless, there is always a continual need to provide new and novel self-stabilizing rotating toys that do not rely on additional rotors to counter the torque of a main rotor. Such a need should include a single main rotor to generate a major portion of the lift. Such self-stabilizing rotating toys should be inexpensive and relatively noncomplex.